This study will provide data to determine the efficacy of M. bovis PPD Tuberculin for the early detection of tuberculosis when and if mammalian tuberculin (OT) is no longer available. Additionally, through the use of clinical pathologic and immunologic tests and the use of equivalent PPD or OT concentrations, various parameters such as erythrocyte sedimentation, lipoproteins, lymphocyte transformation, and skin testing can be efficiently and effectively evaluated.